Coronavirus Immunity: Vaccine Data Hopeful But Unclear — Dare to Know
Coronavirus immunity is the foundation underpinning planned COVID-19 vaccination programs. Find out the status of the ongoing research in this area.
When I was in Grade 9, we were all given as booster shot of the smallpox vaccine. If I remember correctly, we must have been the last cohort to receive the vaccine back in 1974.
Immunization programs eliminated smallpox worldwide in the 70s. The inoculation was no big deal for most of the kids, but I had a bit of a mishap.
Our parents were supposed to have had us all vaccinated once before when we were a year old. My parents told me that the doctor tried to inoculate me at that time.
The Doctor Tried to Inoculate Me at That Time
Unfortunately, the little telltale bump that doctors call the “pustule” didn’t form in my case. That made it unclear if I was adequately immunized, and our doctor deemed it unwise to repeat the procedure.
As a result, there was no record of my immunization when I went for my second inoculation 14 years later. That should have raised a red flag, but the nurse ploughed ahead with the jab because “well, you must have been done…”
The booster shot was a more potent dose, and apparently, I had no immunity from the infant immunization. As a result, I got quite ill, the pustule grew huge, and all the skin on my deltoid muscle turned flaming red. I still have a nasty scar half a century later.
Immune Systems and Vaccine Effectiveness
It all turned out fine, but it was an example of the close connection between our immune systems and vaccine effectiveness. Of course, this consideration will be vital as we deal with the pandemic.
Since the coronavirus outbreak began, people have been clamouring to know if contracting COVID-19 bestows long term coronavirus immunity. In other words, if you’ve had COVID-19, can you catch it again?
The scientific journal Cell published a study last week from the Center for Infectious Disease and Vaccine Research that offers a glimmer of hope. Researchers looked at a group of 20 recovered patients who had tested positive for COVID-19, and they found that they displayed a vigorous immune response, producing T-cells.
Vigorous Immune Response Producing T-Cells
Our adaptive immune system consists of three kinds of cells. We have B-cells that create antibodies, helper T-cells that recognize viruses and killer T-cells that wipe them out.
The researchers found that 70% of the study group had developed killer T-cells, and 100% had generated helper T-cells custom-crafted for SARS-CoV-2, the virus that causes COVID-19. In other words, their systems were well on the way to establishing targeted coronavirus immunity.
Readers will have seen pictures of coronaviruses with their little halo of spikes. Those spikes are how the virus hooks onto and delivers a coronavirus infection to a cell.
T-Cells Targeted Spikes That Hook Onto Our Cells
In more good news, the T-cells the researchers discovered specifically target these spikes. The team also did antibody tests on blood samples that labs had on hand from before COVID-19 started circulating.
They found helper T-cells that could fight SARS-CoV-2 in about half the pre-pandemic samples. The level of antibody protection found suggests that coronavirus immunity to the common cold can help defend against COVID-19.
So, there’s every chance that COVID-19 patients don’t catch it again. More importantly, the results of the study imply that a coronavirus vaccine might be able to wipe it out.
A Vaccine Might Be Able to Wipe It Out
That leads us to another article published last week, this time from the journal Nature. It reviews the status of the various efforts to find an effective vaccine against COVID-19.
As readers will have noticed in the news, the US Biotech firm Moderna announced positive interim clinical data from a phase one study on their vaccine candidate, mRNA-1273. All of the study participants produced coronavirus immunity antibodies, and the vaccine was safe and well-tolerated.
On another front, Oxford University was one of the first institutions to start looking for a COVID-19 vaccine. Their vaccine is in both animal and human clinical trials.
Vaccine Kept a Group of Monkeys from Getting Pneumonia
In the animal trials, the vaccine kept a group of monkeys from getting pneumonia. However, they were still infected with the SARS-CoV-2 virus in their noses. Chinese scientists are also working on a vaccine, and they’ve had the same puzzling result.
The Moderna vaccine produced at least as many helper T-cells as we would find in patients who had recovered from COVID-19. Researchers found this in 25 of the 45 human participants in the Moderna trials.
Not everyone is jumping for joy over Moderna’s announcement, though. Critics say that Moderna needs to publish the source scientific data and not just a cheerleading press release.
Moderna Needs to Publish the Source Scientific Data
Reviewers are also challenging the Oxford results. Although the animals in the study did produce antibodies for coronavirus immunity, the levels were underwhelming.
Some experts think that Oxford’s antibody levels should be higher to afford real protection, while some of their peers disagree. That’s still a matter of opinion because scientists still don’t fully understand how our coronavirus immunity response works.
The other consideration in the Oxford study is that the researchers gave the monkeys a potent dose of the virus to make sure they would be infected. The dosage could explain why the vaccine prevented pneumonia while leaving behind traces of the virus in their noses.
Oxford Vaccine Might Be Strong Enough to Work in Practice
Infections in the field would probably be far less intense than the levels to which the researchers exposed the monkeys. That means that the Oxford vaccine might be strong enough to work in practice.
Although the effectiveness results are unclear, the safety results have been excellent. Neither the Moderna nor the Oxford subjects suffered any adverse events from the tests.
These are all phase one trials that focus mainly on safety. Larger trials in phases two through four will provide researchers with more information on how effective each of the vaccine candidates is in practice.
Every Reason to Move On to Phase Two Trials As Planned
One thing all the experts agree on is that there is every reason to move on to phase two trials as planned. Having excellent safety data but only limited efficacy results is precisely where researchers expect to be at the end of phase one.
All of us must be patient and let the experts carry out their work. Idle speculation at this point will only fuel the infodemic, which is arguably even more harmful to society than the pandemic has been.
The clinical trial process is a tried and true method for bringing all kinds of medicines into general use. It ensures that decision-makers set policy based on science rather than preconceptions or wishful thinking.
Ensures That Decision Makers Set Policy Based on Science
The later phases of the trial should clear up most of the unanswered questions we still have at this point. They’ll accomplish that in a systematic way that scientists and doctors can relate to and apply in their work.
We always have more to learn if we dare to know.
Moderna Announces Positive Interim Phase 1 Data for its mRNA Vaccine (mRNA-1273) Against Novel Coronavirus
Early Coronavirus Immunity Data Fuel Promise for a Vaccine
Targets of T cell responses to SARS-CoV-2 coronavirus in humans with COVID-19 disease and unexposed individuals
Coronavirus vaccine trials have delivered their first results — but their promise is still unclear
Origin of Life Before the Origin of Species — 4 Theories
Origin of COVID-19: Lies, Damned Lies and the Truth
Infodemic: Dangerous Outbreak of Misinformation
Originally published at https://daretoknow.ca on May 27, 2020.